First, with reference to the FIGURE, a laminated ceramic capacitor 1 will be described as a typical example of a laminated ceramic electronic component according to this invention.
The laminated ceramic capacitor 1 includes a laminated body 2 configured with the use of a plurality of dielectric ceramic layers 3 stacked and a plurality of internal electrodes 4 and 5 formed along the specific interfaces between the dielectric ceramic layers 3.
First and second external electrodes 8 and 9 are formed in different positions from each other on the outer surface of the laminated body 2. The laminated ceramic capacitor 1 shown in the FIGURE has the first and second external electrodes 8 and 9 formed respectively on respective end surfaces 6 and 7 of the laminated body 5 opposed to each other. The internal electrodes 4 and 5 include the plurality of first internal electrodes 4 electrically connected to the first external electrode 8 and the plurality of second internal electrodes 5 electrically connected to the second external electrode 9, and these first and second internal electrodes 4 and 5 are arranged alternately with respect to the stacking direction. If necessary, first plating layers 10, 11 and second plating layers 12, 13 are formed on the surfaces of the external electrodes 8 and 9.
In particular, the reduction in size is required for laminated ceramic capacitors, and an approach in which dielectric ceramic green sheets and internal electrode layers are stacked and then subjected to firing at the same time is thus adopted in the production process. For the internal electrodes of the laminated ceramic capacitors, base metals such as Ni are used for reduction in cost.
In recent years, with the further progress in layer thickness reduction for dielectric ceramic layers, the layer thickness reduction for internal electrodes has been also accelerated. However, the reduction in layer thickness for internal electrodes has a problem that the coverage of the internal electrodes is likely to be decreased by spherically agglomerated metal particles, thus creating a need for firing at lower temperatures.
In addition, the demand of various characteristics for laminated ceramic electronic components has also created a need to use a wide variety of metals such as Ag and Cu as metals for internal electrodes. This reason has also created a need for firing at lower temperatures.
Thus, there has been a need for ceramic materials which are able to be fired at low temperatures, and exhibit excellent dielectric characteristics.
For example, Patent Document 1 discloses a barium titanate based dielectric ceramic composition which is suitable for multilayer substrates and laminated ceramic capacitors, and states that the composition is able to be fired at 1000° C. or less.
In addition, Patent Document 2 discloses a barium titanate based dielectric ceramic composition which is suitable for laminated ceramic substrates, and states that the composition is able to be fired at 1000° C. or less.
Patent Document 1: Japanese Patent Application Laid-Open No. 2007-290940
Patent Document 2: Japanese Patent Application Laid-Open No. 2009-132606